1. Field of the Invention
The present invention relates generally to the manufacture of electronic devices. In particular, the present invention is a method for manufacturing flexible thin-film electronic devices to prevent stress on the layer of semiconductor material when the circuit is flexed.
2. Description of the Prior Art
Electronic devices are well known and can be manufactured using any of a number of known techniques. Thin-film solar cells, for example, can be inexpensively manufactured by depositing layers of semiconductor material on flexible substrates using glow discharge deposition and roll-to-roll processing techniques. Continuous roll processing on flexible, aluminum, stainless steel, tantalum, molybdenum, chrome, polyimide-coated stainless steel and polyimide substrates is known. Since solar cells fabricated on these substrates are flexible, they can be mounted to nonplanar objects. In an embodiment described in application Ser. No. 07/165,488, entitled "Light-Rechargeable Battery", filed Mar. 8, 1988 and assigned to the same assignee as the present invention, flexible solar cells are mounted to the cylindrical surface of a battery so as to recharge the battery when it is positioned in ambient light.
Thin-film solar cells are flexed and bent when rolled up following their manufacture or applied to nonplanar articles. One side of the flexed solar cell will be subjected to compressive forces while the opposite side will be stretched and placed in tension. If the semiconductor region or layer forming the solar cell photovoltaic device is at a location which is placed in either tension or compression, its electrical and physical properties can be detrimentally affected. it is known that bond distances in the semiconductor material can be altered and broken by these forces. The result is reduced solar cell efficiency.